In terms of drug resistance caused by CSCs, histone methyltransferase G9a is a potential target for epigenetic therapy of acute myeloid leukemia, and PERK/NRF2 signaling plays a key role in protecting leukemia stem cells (LSCs) from ROS-induced apoptosis, which confers LSCs with resistance to G9a inhibitors. This evidence concerns the gene EHMT2 and acute myeloid leukemia.